This invention relates to the field of shielding radioactive materials and, more particularly, to an improved syringe shield.
The subject matter of this application relates to subject matter disclosed in the copending application Ser. No. 668,531 entitled "Shielded Syringe" filed of even date herewith and assigned to the same assignee as the present invention.
For various types of diagnostic testing it is necessary to inject radioactive materials into a patient. It is well recognized that technicians who handle these materials need protection against the perils of cumulative ionizing radiation exposure, so provision is commonly made for shielding the materials until such time as they are injected into the patient. Toward this end, various types of syringe shields have been developed. The typical prior art syringe shield includes a lead cylinder that fits over a syringe, the lead body having a window of leaded glass which allows the operator to see the scale on the syringe housed in the lead cylinder.
There are a number of disadvantages to presently available syringe shield designs. Some available units have a simple cylindrical casing which does not provide adequate shielding frontwardly or rearwardly of the syringe length. A further problem is that there is no standardization of syringe sizes, and even syringes having the same volume often have different physical dimensions. For example, a 10 cc syringe may have various possible diameters depending on the particular manufacturer. Thus, special provision is generally made to fit a syringe shield to the different possible syringe sizes. For example, in one prior art design the syringe shield is provided with a "set screw" which adjustably protrudes into the syringe shield's bore and engages the syringe so that it cannot move around within the syringe shield. The use of this technique involves some inconvenience and can occasionally cause breakage of the syringe.
The presence of a heavy shielding body, typically lead, is also problematic from the standpoint of unpleasantness of use. An unfinished lead exterior tends to become dirty and contaminated and is unsuitable for hospital conditions, whereas provisions for special finishing or plating may involve expense or introduction of unnecessarily cumbersome structures.
It is an object of this invention to provide a syringe shield which is responsive to the above recited problems of the prior art, while still being economical to manufacture and convenient to use.